Decades of discovery

The shutdown of the Tevatron accelerator marks a turning point in physics — and two OSU scientists have been along for the ride

by Pam Frost Gorder

OSU physicists Brian Winer, left, and Richard Hughes first began work with the Tevatron at the Fermi National Accelerator Laboratory as undergraduate research assistants in the 1980s.

The world’s second-largest particle accelerator may have shut down permanently on Sept. 30, but for Brian Winer and Richard Hughes, the science goes on.

The Ohio State physicists are helping to close a chapter on 20th century physics and open a new chapter to whatever lay beyond.

Winer and Hughes worked at the particle accelerator at the Fermi National Accelerator Laboratory in Batavia, Ill., for more than 25 years. They arrived as undergraduate research assistants in the 1980s and returned as doctoral students. Now as professors, they lead their own experiments.

Their goal: To find evidence of exotic particles that were predicted to exist since the 1960s.

For decades, this particle accelerator – called the Tevatron – smashed protons and antiprotons together at high speed to break them apart and release rarely seen sub-atomic particles such as quarks. Millions of collisions per second created billions of fragments of every imaginable size and type of particle. Scientists are still carefully sifting through it all.

Over their careers, Winer and Hughes developed unique computing strategies for analyzing the deluge of data that the collisions produced. Another year will likely pass before they can work through the information backlog.

There have already been victories along the way.

“Definitely, the high point was when we knew we found the top quark,” Winer said.

Quarks are the building blocks of protons and neutrons. Physics theory predicted the existence of six different types of quarks, and the top quark was the last one to be verified.

To isolate the tiny quark from all the other particles, the physicists employed neural networks – computer algorithms that mimic the learning process of the human brain. The two led a series of experiments that hinted of the particle’s existence for years before they officially announced its discovery in 1995.

Another theoretical particle remains to be seen, and it’s of a completely different sort: The Higgs boson, which scientists believe gives mass to all other particles.

Winer and Hughes were the first to apply their neural network technique to search for the Higgs, and now all researchers worldwide who are in a race for the discovery are using similar methods.

A year’s worth of Tevatron data remains to be analyzed, and Hughes hopes that evidence of the Higgs is hiding in it.

“I feel like we’re in the same place we were about six months before we found the top quark,” he said. “We’re seeing hints that we’re close.”

“Our goal is to make our final results public by March 2012,” Winer agreed.

While the two Ohio State physicists continue to look for the Higgs at the Tevatron, their specialized skill set is in demand. They were recruited to join a competing experiment at the world’s biggest accelerator, the Large Hadron Collider (LHC) in Switzerland.

Winer and Hughes can’t share information from the Tevatron team with the LHC team, and vice versa. They must remain entirely impartial.

Well, almost entirely impartial.

“The Tevatron is winding down, while the LHC is just getting started,” Hughes explained. “It has a long and glorious time ahead of it, with untold discoveries beyond the Higgs that could emerge over the next 20 years. We would love for the Tevatron to come in first, and the LHC just barely second.”